The present invention relates to a communication system for exchanging data between data recipients and data generators.
Today, vehicles such as agricultural working machines include a large number of electronic monitoring devices which exchange data via an internal bus system, or which exchange data with external communication devices via this bus system. Among many other things, an essential purpose of this data exchange is to monitor and control the mode of operation of the particular vehicle and its working units, and to ensure that highly diverse monitoring functions are performed properly. In the agricultural application, particular significance is attributed to ensuring that the settings for the operating parameters of the working units of an agricultural working machine are optimal, and, in particular, to monitoring the service life of components of the vehicle.
Depending on the configuration of the data generation and transmission systems, sensor systems internal to the machine detect operating states of the vehicle and its working units. These operating states are compared in internal or external data processing devices with characteristic curves and/or defined operating states which are stored therein; results data are generated which are then used to optimize various parameters of the vehicle and its working units. In this context it is also known to monitor the service life of certain working units and their components using internal or external diagnostic systems, and, depending on the structure of the diagnostic system, to identify any disturbances that occurred and identify their causes, or to diagnose information about the remaining services lives of components.
The numerous monitoring and control functions described above are typically carried out by control devices which, depending on the design stage and development status, include software modules which must be updated regularly. With regard for adjusting operating parameters in a manner that is controlled via characteristic curves, this regular updating is carried out because the particular control devices must be reprogrammed depending on crop material parameters and efficiency characteristic values of the agricultural working machine; in the simplest case, the reprogramming includes selecting a characteristic curve which is stored in a data processing device, and which then adapts the functionality of the particular control device to the new basic conditions. In every case, it is necessary for the data exchange to take place between the appropriate control devices and data processing devices, and in the correct direction.
From the prior art, e.g. DE 198 49 810, it is known that flash memories for programming control devices are designed in such a manner that user access rights and serial numbers of control devices are stored in them. If a user wants to reprogram certain control devices, he must identify the particular control device by entering and verifying the access right and the serial number. Given that safety considerations are paramount in communications of this type, a specific communication route is determined by explicitly entering identification data and comparing it with identification data that are stored in the flash memory; via this communication route and in a next step, communication takes place between a control device and a data processing device which is designed, e.g. as a diagnostic device. Communication systems designed in this manner have the disadvantage in particular that an individual, e.g. the operator of the diagnostic device, must always first enter data in a communication medium, based on which communication may then take place. This slows the communication process, binds it to a certain communication medium, and makes it complex and expensive since it requires operator intervention.
DE 195 41 816 makes known a further communication system with which a diagnostic device may communicate with the control device of a vehicle. To ensure that the control device may communicate with the control devices of various vehicle types or models of a vehicle type, the diagnostic device is designed such that it may change its identity using software which is stored on a memory cassette, in a manner such that it may communicate with highly diverse types of control devices. Systems of this type have the disadvantage, however, that the particular application—in this case, the diagnostic device that is adapted specifically to the particular vehicle type and its control devices using software—must include very specific information about the control device to be diagnosed, the data communication route, and the type of communication medium. As a result, the use of the diagnostic system becomes that much more inflexible the fewer the number of vehicle-specific software packages is that are stored on the memory cassette. In addition, increasing the number of vehicle-specific data packets that are stored on the memory cassette increases the costs of the memory cassette considerably.